March 20, 2012 -- Taking vitamin E supplements may not help when it comes to preventing heart failure among women.

A new study shows that vitamin E supplements had no effect on women's risk of developing heart failure.

It's the first large-scale study on the effectiveness of vitamin E in preventing heart failure.

Vitamin E is one of a group of nutrients known as antioxidants, which are thought to help protect the body from oxidative damage to its cells.

But some previous studies on vitamin E and heart failure have suggested that the antioxidant may actually increase the risk of heart failure, and other studies have had conflicting results.

Heart failure affects more than 5.7 million people in the U.S. It's a chronic, progressive condition in which the heart is no longer able to pump enough blood to meet the body's needs.

Vitamin E Doesn't Help Heart Failure

In the study, researchers followed a group of nearly 40,000 women aged 45 and older in the Women's Health Study for an average of about 10 years.

The women took 600 international units (IU) of vitamin E or a placebo every other day.

During the study, 220 episodes of heart failure were diagnosed. The results showed that taking vitamin E supplements had no impact on the women's risk of developing heart failure.

The researchers say the results show that vitamin E does not appear to help or hurt the risk of developing heart failure among women.

"These results underscore the importance of focusing on other primary prevention measures proven to reduce the risk of future [heart failure], including effective control of blood pressure and the primary prevention of [heart] disease," researcher Claudia Chae, MD, MPH, of Massachusetts General Hospital, and colleagues write in Circulation: Heart Failure.